If (x + 1/x)² = 3, then the value of (x^72 +x^66 + x^54+ x^24+ x^6 + 1) is

asked by guest
on Jan 22, 2025 at 1:49 am



MathBot Answer:

x72+x66+x54+x24+x6+1{1+(32i2)66+(32i2)54+(32i2)24+(32i2)6+(32i2)72,1+(32+i2)72+(32+i2)6+(32+i2)54+(32+i2)24+(32+i2)66,1+(32i2)66+(32i2)6+(32i2)54+(32i2)24+(32i2)72,1+(32+i2)72+(32+i2)54+(32+i2)24+(32+i2)6+(32+i2)66}x^{72} + x^{66} + x^{54} + x^{24} + x^{6} + 1 \in \left\{1 + \left(- \frac{\sqrt{3}}{2} - \frac{i}{2}\right)^{66} + \left(- \frac{\sqrt{3}}{2} - \frac{i}{2}\right)^{54} + \left(- \frac{\sqrt{3}}{2} - \frac{i}{2}\right)^{24} + \left(- \frac{\sqrt{3}}{2} - \frac{i}{2}\right)^{6} + \left(- \frac{\sqrt{3}}{2} - \frac{i}{2}\right)^{72}, 1 + \left(- \frac{\sqrt{3}}{2} + \frac{i}{2}\right)^{72} + \left(- \frac{\sqrt{3}}{2} + \frac{i}{2}\right)^{6} + \left(- \frac{\sqrt{3}}{2} + \frac{i}{2}\right)^{54} + \left(- \frac{\sqrt{3}}{2} + \frac{i}{2}\right)^{24} + \left(- \frac{\sqrt{3}}{2} + \frac{i}{2}\right)^{66}, 1 + \left(\frac{\sqrt{3}}{2} - \frac{i}{2}\right)^{66} + \left(\frac{\sqrt{3}}{2} - \frac{i}{2}\right)^{6} + \left(\frac{\sqrt{3}}{2} - \frac{i}{2}\right)^{54} + \left(\frac{\sqrt{3}}{2} - \frac{i}{2}\right)^{24} + \left(\frac{\sqrt{3}}{2} - \frac{i}{2}\right)^{72}, 1 + \left(\frac{\sqrt{3}}{2} + \frac{i}{2}\right)^{72} + \left(\frac{\sqrt{3}}{2} + \frac{i}{2}\right)^{54} + \left(\frac{\sqrt{3}}{2} + \frac{i}{2}\right)^{24} + \left(\frac{\sqrt{3}}{2} + \frac{i}{2}\right)^{6} + \left(\frac{\sqrt{3}}{2} + \frac{i}{2}\right)^{66}\right\}


ii is the imaginary unit, defined as i2=1i^2 = -1.

By substituting this value into the expression, we find that: x72+x66+x54+x24+x6+1=1+(32i2)66+(32i2)54+(32i2)24+(32i2)6+(32i2)72=1+(32i2)66+(32i2)54+(32i2)24+(32i2)6+(32i2)72\begin{aligned}x^{72} + x^{66} + x^{54} + x^{24} + x^{6} + 1 &= 1 + \left(- \frac{\sqrt{3}}{2} - \frac{i}{2}\right)^{66} + \left(- \frac{\sqrt{3}}{2} - \frac{i}{2}\right)^{54} + \left(- \frac{\sqrt{3}}{2} - \frac{i}{2}\right)^{24} + \left(- \frac{\sqrt{3}}{2} - \frac{i}{2}\right)^{6} + \left(- \frac{\sqrt{3}}{2} - \frac{i}{2}\right)^{72}\\&= 1 + \left(- \frac{\sqrt{3}}{2} - \frac{i}{2}\right)^{66} + \left(- \frac{\sqrt{3}}{2} - \frac{i}{2}\right)^{54} + \left(- \frac{\sqrt{3}}{2} - \frac{i}{2}\right)^{24} + \left(- \frac{\sqrt{3}}{2} - \frac{i}{2}\right)^{6} + \left(- \frac{\sqrt{3}}{2} - \frac{i}{2}\right)^{72}\end{aligned}